<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
         * {
            margin: 0;
            padding: 0;
        }

        li {
            list-style: none;
        }

        img {
            width: 100%;
        }

        .box {
            width: 249px;
            height: 210px;
            margin: 50px auto;
            /* 消除溢出在外面的播放键 */
            overflow: hidden;
            /* overflow:visibility;  出现 */
        }
        
        .box p {
            color: #3b3b3b;
            padding: 10px 10px 0 10px;
        }
       .pic {
            position: relative;
        }
        /* 分析使用定位来水平居中这个按钮  --子绝父相 */
        .play {
            /* 在网页中不占位置 display没有过渡效果*/
            display: none;
            /*opacity在网页中占位置 --透明到出现opacity有过渡效果*/
            /* opacity: 0; */
            position: absolute;
            left: 50%;
            top: 50%;
            transform: translate(-50%, -50%);
            transition: all .5s;
        }

        .box li:hover .play {
            opacity: 1;
            /* 除了出来  还要缩小 transform 注意他的层叠性 */
            transform:  translate(-50%,-50%) scale(0.2);
        }
    </style>
</head>

<body>
    <div class="box">
        <ul>
            <li>
                <div class="pic">
                    <img src="./images/party.jpeg" alt="">
                    <img class="play" src="./images/play.png" alt="">
                </div>
                <p>【和平精英】“初火”音乐概念片：四圣觉醒......</p>
            </li>
        </ul>
    </div>

</body>

</html>